Neurons form an intricate network through which electrical impulses flow and connect with each other at a point called the synapse. What does this network primarily do?

• A. Storage of genetic material
• B. Filtration of blood
• C. Hormone production
• D. Transmission of electrical impulses across synapses

Answer: (D)

The brain’s communication network exists to transmit electrical impulses across synapses, enabling neurons to pass signals rapidly and coordinate body activities. An impulse travels along a neuron to its end, where it triggers neurotransmitter release across the synapse, exciting or inhibiting the next neuron and continuing the message. This signaling underpins movement, perception, thought, and reflexes. The other options describe separate bodily functions—genetic material storage in the nucleus, blood filtration by the kidneys, and hormone production by the endocrine system—so they don’t capture the network’s primary purpose of neural communication.